Controller for electric motors.



No. 7oa,|5s. Patented sept. 2, |902.

` F. A. MERmcK & E. w. sTuLL.

CONTROLLER FOR ELECTRIC MOTORS.

(Application led Jan. 2, 1902.; (No Mcdel.)

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CIIIZEj'm/E' WITNESSES UNITED STATES PATENT OEETQE.

FRANK A. MERRICK AND EMMETT IV. STULL, OF JOHNSTOW'N, PENNSYLVA- NIA,ASSIGNORS, BY MESNE ASSIGNMENTS, TO IVESTINGIIOUSE ELEC- TRIC ANDMANUFACTURING COMPANY, OF PITTSBURG, PENNSYLVANIA, A CORPORATION OFPENNSYLVANIA.

CONTROLLER FOR ELECTRIC MOTORS.

SPECIFICATION forming part of Letters Patent No. 708,158, datedSeptember 2, 1902.

Application tiled January 2, 1902. Serial Nol 88,092. (No model.)

To @ZZ whom, it may concern: lish themselves, the direction of the linesof Be it known that we, FRANK A. MERRICK force being substantiallyperpendicular to o and EMMETT VV'. STULL, of Johnstown, in the thedirection of maintenance ot' the arc and county of Cambria and State ofPennsylvania, therefore, as is well known, most effective in 5 haveinvented a new and usefulImproVement extinguishing action.

in Controllers for Electric Motors, (Case 13,) Our invention alsoconsists in the novel of which the following is a full, clear, andconstruction, combination, and arrangement. exact description, referencebeing had to the of. parts, all as hereinafter described, andaccompanying drawings, which form a part pointed outin the appendedclaims, reference Io of this specification. being` had to theaccompanying drawings, in

This invention has relation to controllers whichfor electric motors, andis more particularly Figure l is a front view of a controller emdesignedto provide electromagnetic means bodying the invention with a portion ofthe of improved character 'for extinguishing or casing removed, and Fig.2 a section on the 15 blowing out arcs at the controller conline 2 2 ofFig. l.

tacts. Considerable difficulty exists in pro- In the figures, the letterA designates the viding in thelimited space available in a concasing ofthe controller; B, the contact-cartroller-casing and in View of thedifficulty of rying control-drum carried by a shaft; b, the preventingmagnetic leakage a blow-out magcontacts on said drum C C,contact-lingers,

2o net and magnetic circuit which shall be suffiand'D the drums of areversing and cut-out ciently etective throughout the length of theswitch. This last-named switch does not encontroller-drum unless thestrength of the ter into the present invention and is shown 7c magnet bemade very much greater than only for completeness. Its drum beingprefwould otherwise be necessary for the Work to erably of wood does notaiect the magnetic z5 be performed. circuit hereinafter described.

The presentinvention is designed to reduce E designates the blow-outcoil, which may largely the loss in efficiency dueto magnetic beconnected in circuit in any usual or deleakage and also to provide for amore unisirable manner. This coil is placed behind form distribution ofthe magnetic circuit the drum B and is wound about a core F,

3o throughout the full contact length of the which mayform an integralprojection from drum. the rear portion of the casing A, as shown in Inaccordance with the invention we ar- Fig.2.Itisextendedthroughthecoiltoaposi- 8o range the blow-out coil adjacentto the cention opposite one side of the drum, and firmly tral portion ofthe drum and secure to the bolted or otherwise rigidly secured theretois 3 5 core of the said coila vertically-extended poleapole-piece G.This pole-piece preferably conpiece, whose end portions are made tocarry sists of a flat barof magnetic material presentthe bearings forthe drum, thus providing a ing a flat side toward the drum. Its lowermagnetic circuit from the coil directly into end portion is bent inunder the drum and the drum at both its ends. Furthermore, the seats thelower bearing (j for its shaft. The

4o body of the drum itself being of magnetic upper bearing t', ofmagnetic material, is material there is more or less magnetic flux alsocarried by said pole-piece, which is steadacross the air-space betweenthe pole-piece ied by being secured to the top A of the cas- 9o and drumthroughout the entire contact ing bya bolt g2 or othersnitable means.Belength of the latter. The return-circuit is hind the contact-ngers Cthe door portion 45 made through the casing of the controller, of thecasing is formed with a vertical reinand said casing is so constructedas to diforcement l-I, of magnetic material, which reet the flux fromthe drum to the casing serves to direct and concentrate the lines ofthrough the points where arcs tend to estabforce through thearcing-spaces of the drum at substantially right angles, thereturn-circuit being from the piece H around through the casing to thepole-piece. By making the pole-piece G carry the shaft-bearings leakagethrough such bearings is prevented. The top of the casing is formed ofbrass or other non magnetic material, and consequently there is nomagnetic leakage through it from the upper end of the pole-piece.

It is obvious that various mechanical changes may be made in theconstruction and arrangement of the various parts Without affecting theinvention. Hence We do not Wish to limit ourselves to the preciseconstruction and arrangement herein shown and described.

Having thus described our invention, what We claim as new, and desire tosecure by Let- I ters Patent, is-

l. In a controller for electric motors, the combination with a casingformed in part of magnetic material, and a controller-drum whose bodyand shaft are also of magnetic material, of a blow-out coil, a coresupporting said coil, and a pole-piece carried by said core and carryingthe bearings for the said shaft.

2. In a controller for electric motors, the combination With acontact-carrying drum having a body of magnetic material, of a blow-outcoil adjacent to the central portion of said drum, a pole-piece carriedby the said core, and carrying the bearings for the shaft of said drum,and a casing arranged to complete the magnetic circuit through the saiddrum. l

3. In a controller for electric motors,ablow out coil adjacent to acontact-carrying drum of the controller, a pole-piece carried by thecore of said coil, and bearings for the shaft of said drum carried bythe said pole-piece.

4. In a controller for electric motors, the combination of a casinghaving its body portion formed of magnetic material, a contactcarryingrdrum having its body and shaft of magnetic material, a blow-out coiladjacent to the central portion of said drum, a core for said coilcarried by the said casing, a polepiece for said coil carried by thecasing and itself carrying the bearings for the said shaft.

5. In a controller for electric motors, the combination with acontact-carrying drum having its shaft and body portion composed ofmagnetic material, a blow-out coil, and a pole-piece secured to the coreof said coil and extending in opposite directions therefrom parallelwith and adjacent to the said drum, and bearings for the drum-shaftcarried by the said pole-piece.

In testimony whereof We have affixed our signatures in presence of twoWitnesses.

FRANK A. MERRICK. EMMETT W. STULL.

Witnesses:

CORA G. (Jox, H. W. SMITH.

